Because the new version of Fall from Heaven for Civ4 just came out.

Among the new features: global spells. Not just your pansy little “Fireball 2″ these:

Mercurians- Divine Retribution: Does damage to all Undead and Demonic units in the world
Sheaim- Worldbreak: Does damage to all units in cities, forest fires start around the world
Ljosalfar- March of the Trees: All forests in the players empire turn into Treants for 3 turns, when the Treants die they return to forests in the plot (if it can support a forest)

That’s right – your elves can now go all Treebeard on people. It’s almost enough to forgive them for being, well, elves.